Recovery of hydrocarbon oil



y 1949- c. E. HEM'MINGER 2,471,107-

RECOVERY OF HYDROCARBON OIL Filed Dec. 28, 1945 (2A (WED h qwors $577252 77'? OUTLET tai -:1? SL022) LINE I v '53 .STRIPPEZ 50 I V E N627 4- 52 Q MEAT D {HOT GASES 5 B RNER f Patented May 24, 1949 UNITED STATES RECOVERY OF HYDROCARBON OIL Application December 28, 1945, Serial No. 637,613

1 Claim. (Cl. 19614) TENT OFFICE My invention relates to the novel features described in the following specification and claim considered in connection with the accompanying drawing.

I am aware that prior to my invention others had proposed recovering available hydrocarbons oils from mineral sources other than crude petroleum oil deposits. For example, it was known that a hydrocarbon oil could be obtained from appear in the following more detailed description and claim. In the drawing I have shown diagrammatically an apparatus layout in which a preferred modification of my invention may be carried into effect.

Referring in detail to the drawing, tar sands such as Athabaska sands found, for example, near Edmonton, Alberta, Canada, and its Vicinity and containing to bitumen enter the system Shale by subjecting the shale (preferably in at 10 through line I and are first passed through a drier lea-st roughly ground condition) to a pyrolytic 3. In the drawing the drier 3 is shown diagramtreatment for an extended period of time. Simimatically and while it may have many forms, it larly, it was known prior to my invention that preferably is an inclined drum which may be available hydrocarbon oils could be obtained from rotated by driving means (not shown) through oil sands by subjecting the said sands to a similar 15 which the tar sands pa rather Slowly by gravity heat treatment for a suficient period of time to against a current of flue gas which enters the efiect the desired conversion. There are other opposite end of the drum 3 from which the tar known materials as tar sands, peat, lignite and sands enter; namely, through line 5. Of course, coal from which hydrocarbon oils could be recovh Purpose Of th s preliminary drying is p ered from minerals by heating the minerals in rily to remove moisture and preheat the sand by suitable retorts and the like for a sufficient period Waste heat in the System, as e plained more fully of time to cause vaporization of the hydrocarbon hereinafter. The dried tar sand, at a tempera oils therein contained and the recovery of the ure of o ab to preferably same. around 600 F. is then discharged from the drum My present improvements in their essence go to 2 5 3 through a line Ill and through sealing star the concept of recovering hydrocarbon oils from feeder H into an extraction zone [3 where it tar sands or other bituminous-carrying solids in contacts hot hydrocarbon vapors produced in a which the crude oil-bearing sand or bituminous subsequent portion of the opera ion, as will later material is subjected to an extraction, using as app n the rawin he extrac ion zone I3 is the extracting solvent a portion of the oil recovshown as a screw-mixing conveyor and by the ered from a previous operation in which 011 i operation of the flights which are driven in known recovered from the said sands. manner by driving means (not shown) the dried The main object of my present invention i t tar sands are urged through the extraction zone p ovide a method for efliciently and more cheaply while subjected to the influence of the hot hydrorecovering available hydrocarbon oils from tar Carbon Vapors introduced u h ne l5 at a sands and/or other bituminous-carrying solids. pe t 5 to 1000 The Screw- A more specific object of my invention is to exmiXihg C y has a discontinuous Screw, tract a hydrocarbon oil from tar sands using as an broken into several fligh s, to p O O e m n extractant hot hydrocarbon vapors recovered The mixture of hot oil vapors and sands in l3 from a previousoperation in which oil was refirst causes the former to partially liquefy and covered from said sands. the condensate serves to extract oil from the Another object of my present invention is to latter to form a slurry of oil and bituminous solprovide a continuous method for extracting ids, which is Withdrawn from the extraction zone hydrocarbon oils from tar sands and the like in through line 2i] and discharged through star a system generally operated at elevated temperafeeder 2! into a quiescent settling zone 22. In tures in which the heat necessary to maintain this extraction step to of the bitumen the system in operation is obtained by burning and/or oil originally in the sand is removed. materials formed within the system. Simultaneously, however, from an upper portion As a corollary to the next preceding object, it of the extraction zone, hydrocarbon oil for prodis also an object of my invention to provide means 50 uct recovery is Withdrawn through exit pipe 23.

for cracking hydrocarbon oils boiling above the gasoline range as a part of the system and supplying the heat necessary for the cracking by burning combustibles formed during the process. Other and further objects of my invention will The vapors in line 23 consist of the lighter hydrocarbons boiling up to about 600 F. They are separated by distillation and recovery equipment (not shown). The vapors in line 23 are the uncondensed portion of those which entered through line [5. The preheated solids are further heated by contact with the hot oil vapors, which enter through line l5 (as stated) and simultaneously, at least a portion of the said vapors are condensed by the cooling effect of the solids providing therefore in the mixing device the extracting oil in liquid phase.

Referring again to settler 22, the slurry is permitted to remain in the said settler until stratification occurs to form a lower solids phase and an upper liquid phase. The latter liquid phase, which may contain some fine sand, say up to 0.1% by weight, is withdrawn through line 25, carrying a pump 26, and impelled by the latter into a fired coil or the like 30 where it is heated to cracking temperatures and thence discharged into a knock-down drum 32 from which cracked vapors are taken oif overhead through line 15 and caused to pass through the mixing device or extractor l3, as previously indicated. From the bottom of drum 32 tar is withdrawn through line 35. The cracking in 3D is preferably thermal. However, the oil cracking process in 3b which produces heated, cracked vapors may be a catalytic process, preferably one in which the heat is provided by burning the carbon, formed in cracking, from the catalyst as in the fluid process. The same may also be a thermal or fluid coking operation where only hot vapors and coke are produced. The particular type of process to give the hot cracked vapors is not the essence of this invention for either the cracking or coking process will give the desired hot vapors. In other words, the oil which is extracted from the sands is ordinarily 'a relatively heavy or high boiling product, at least in part, and this mate rial is subsequently cracked at 3!) to give, together with the tar, a heavy gas oil, a lighter gas oil and some gasoline It is primarily the heavier gas oil fraction of the-cracked vapors which is the extracting medium in l3. On the other hand, a product for recovery may be taken off from line 25 via line 48. This product is a heavy residuum oil which may be sold as a fuel or processed for lighter hydrocarbons such as gasoline and heating oil. It is believed to be obvious that in actually starting up the process which I have described up to this point, that hot hydrocarbon vapors from an external source must be introduced into the system via I52) into line l5 but after the process has proceeded to the point where hot cracked vapors are produced, the external source of the hydrocarbon vapors in line 55 may be discontinued.

Referring to the settler 22, the spent bituminous solids (i. e. the spent sands) are withdrawn as a slurry from the bottom of said settler through line 45 and discharged into a stripper ll where they are heated with an inert gas, steam or heated recycle hydrocarbon gases introduced through line 59 for the purpose of stripping volatile material therefrom and the vapors from this step are withdrawn through line 52, forced through a pump 53 for delivery through line 55 to line 23 where they are processed with similar products in line 23. Stripper if, like drier 3, may have the form of an inclined rotatable drum through which the slurry flows by gravity countercurrent to the heated inert gas. The inert gas may, for example, be flue gas produced in another part of the system. The stripped solids are withdrawn from the stripper 47 'through line 60 and discharged into a burner 62, which burner may have the form of an inclined rotatable drum wherein the solids containing carbon pass by gravity towards the outlet against a current of air introduced through line 65. The air causes combustion of the carbonaceous material still retained by the bituminous solids and the fumes thus formed are withdrawn through line 5 and discharged into drier 3, as previously described. The spent solids are rejected from the system by drawoff pipe 61.

It will be noted that in the previous description the oil recovered by extraction from the gas was preferably thermally cracked. This has the advantage that the tars formed in the oil may be removed giving a clear stream of the desired boiling range for the extraction operation in mixer 13. Furthermore, the heat content of the cracked vapors is utilized to maintain the proper temperature in the extractor which preferably is of the order of 300 to 800 F. This type of oil extraction is preferred over water flotation or oil and water separation of sand and bitumen because high temperatures may be maintained without the use of high pressures. Pressures in the order of 2 to 50 lbs/sq. in. gauge ma be used in my process. It is noted that the oil used for extraction is chemically substantially the same as that extracted, differing in that it has a lower boiling range due to the cracking. 'Con sequently, more complete extraction is obtained because it is of the same nature, either highly naphthenic, phenolic, parafiinic, depending only on the nature of the oil associated with the solid undertreatment.

To recapitulate, I have shown in the drawing and described in words hereinbefore an efficient method for recovering a heating oil, including gas oil from tar sands and the like, by a continuous process in which hot cracked vapors are used in an extraction zone to dissolve out hydrocarbon oil from the bituminous solids, an extraction operation which may be carried out without resorting to superatmospheric pressure. Other attributes of the system include utilization of the fuel content of the spent extracted material for the purpose of making the system self-sufficient regarding heat requirements, The product in line 23 may be discharged into an absorber tower (not shown) and normally gaseous hydrocarbons recovered from said tower may be burned in heater 3% to supply at least a portion of the required heat. As previously indicated, other attributes of my invention include using a thermally cracked oil from which the tar has been removed as the extracting liquid. In the drawing I have shown recycling through line [5a a portion of the product withdrawn from settler 22. This, however, is a less preferred modification of my invention for the reasons indicated.

As stated, it is obvious from the foregoing description that in order to start operations in the system which I have shown, oil from an extraneous source such as light gas oil or a heavy naphtha must be introduced into the present system through line 15, but thereafter the process is designed to produce its own extracting oil.

Numerous modifications of my invention may be made by those who are familiar with the oil refinin art generally without departing from the spirit thereof.

What I claim is:

A continuous method for recovering hydrocarbon oil from bituminous solids which comprises subjecting said bituminous solids to the influence of heated gases in a drying zone, withdrawing the thus dried bituminous solids from the drying zone, discharging them into :an extraction zone, contacting said bituminous solids in the last-named zone at an elevated temperature with vaporized normally liquid hydrocarbons preheated at least to extraction temperature while agitating the said bituminous solids whereby hydrocarbon material contained in said bituminous solids is extracted therefrom, recovering for product from said extraction zone a gasiform hydrocarbon material containing hydrocarbons and withdrawing from said extraction zone spent bituminous solids in the form of an oil slurry, discharging the said slurry into a settling zone, permitting the slurry to remain resident in the settling zone for a sufiicient period of time to permit stratification to form a lower spent bituminous solids phase and an upper liquid phase, withdrawing the liquid phase from the said separating zone, reheating at least a portion of said liquid partially to vaporize the same, employing said heated vapors to contact the dried bituminous solids in the said extraction zone, withdrawing the said spent bituminous solids from the settling zone, discharging them into the stripping zone where they are treated with a hot inert gas to recover a further portion of hydrocarbon vapors, with- 6 drawing the stripped solids from the stripping zone, dischargin them into a burning zone, causing combustion of fixed carbon contained in said solids in said burning zone, withdrawing the gaseous combustion products from said burning zone and discharging them into said drying zone Where they contact the fresh bituminous solids. CHARLES E. HEMMINGER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 617,226 Cooper Jan. 3, 1899 1,327,572 Ryan Jan. 6, 1920 1,458,983 Kirby June 19, 1923 1,514,113 Trumble Nov. 4, 1924 1,607,977 Armstrong Nov. 23, 1926 1,778,515 Hampton Oct. 14, 1930 1,940,725 Morrell Dec. 26, 1933 2,132,441 Rosenthal Oct. 11, 1938 2,222,389 Riggs Nov. 19, 1940 

